--vectorator
printh("\n\n\n\n\n\n\n\n\n")

instructions = {
"return",
"jump",
"scale",
"rotate",
"draw",
"draw_abs",
"move",
"place"
}

function empty_state()
	return {
		stack={{"main", 1}},
		scale=1,
		position={0,0},
		rotation=0
	}
end

state = nil

function vectorate(mem, callbacks)
	state = empty_state()

	while true do
		height = #state.stack
		bank = state.stack[height][1]
		index = state.stack[height][2]
			
		state.stack[height][2] += 1
		
	 instruction = mem[bank][index]
		perform(state, instruction, callbacks)
		
		//printh(list_table(state))
		if (#state.stack == 0) break
	end
end

function perform(s, op, cb)
	if cb == nil then
		cb = {pre=nil, post=nil}
	end
	
	if cb.pre ~= nil then
		cb.pre(s, op)
	end
	
	if op[1] == "return" then
		s.stack[#s.stack] = nil	
	elseif op[1] == "jump" then
		if m[op[2]] ~= nil then
			add(s.stack, {op[2], 1})
		end
	elseif op[1] == "scale" then
		s.scale = s.scale * op[2]
	elseif op[1] == "rotate" then
		s.rotation += op[2]
	else
		x = s.scale * (
					op[2]*cos(s.rotation) 
			- op[3]*sin(s.rotation))
		y = s.scale * (
					op[2]*sin(s.rotation) 
			+ op[3]*cos(s.rotation))
		
		if op[1] == "move" then
			s.position[1] = s.position[1] + x
			s.position[2] = s.position[2] + y	
		end
		
		if op[1] == "place" then
			s.position[1] = x
			s.position[2] = y
		end
		
		if op[1] == "draw" then
			line(s.position[1], s.position[2], 
				s.position[1]+x, s.position[2]+y,
				10)
			s.position[1] += x
			s.position[2] += y
		end
		
		if op[1] == "draw_abs" then
			line(s.position[1], 
				s.position[2], 
				x, y, 
				10)
			s.position[1] = x
			s.position[2] = y
		end
	end
	
	if cb.post ~= nil then
		cb.post(s, op)
	end
end